I'm not sure when it was done — and I don't know where to find a copy of the whole thing (does anyone?) — but Stephen Sondheim did a TV special some years ago where he taught students how to sing some of his songs. A while ago, in this posting, I linked to a clip of him critiquing a brave young woman who was attempting to sing "Send in the Clowns," not only in front of its composer but in a public spectacle where he was expected to find fault with her performance. Here, three brave students take on one of Sondheim's most difficult songs with him playing teacher. The most interesting thing about this clip is the look on his face when he hears something he likes. It's a look I've seen on the face of every great songwriter I've been able to look at when he's hearing his song the way he wants to hear his song.